Method of fabricating structural members



March 1 1927.

M. A. BAKER METHOD OF F-ABRICATING STRUCTURAL MEHBERS z'sheets-shee't 1 Filed Oct. 8, 1925 attozmq Q March 1 1927.

. 1,619,232 7 M. A. BAKER METHOD OF FABRICATING STRUCTURAL MEMBERS Filed oct. a, 1925 3 Sheets-Sheet 2 oo000o o00 4 attozwu d- March 1,.1927. I 1,619,232

' v M. A. BAKER I METHOD OF FABRICATING STRUCTURAL MEMBER-S Filed Oct. 8, 1925 5 Sheets-Sheet 5 Paten te d Mar. 1 1927.

* UNITED sr res m MUM-r MILO 'ABAKER, or Los ANGELES, CALIFORNIA.

METHOD OF FABRICATING srnncrnimn MEMBERS.

Application filed October This invention relates to methods of fabricating structural members, 7 v

This method of fabricating. structural members is particularly adapted to the con- 5 struction of large steel or iron members such as built-up girders, columns, and other structural units employed in buildings, bridges, etc.,in other words, structural members built up ofplates and angles, channels,

or the like. Such members, by reason of their great size, weight and diversity of form, render impracticable the use of jigs or holders of the type commonly employed for assembling and machining small or medium sized articles, or for quantity production of like parts. By the use of this method I secure greater accuracy and asuperior quality of work than that resulting fromthe meth ods usually employed for fabricating large structural members. g I V I A very important object attained by the performance of this new method of fabricating structural steelor' ironis the saving effected in thetime and labor consumed in laying out the work for riveting and also in the time of actual drilling; By this method I a plurality of parts are assembled and clamped together before drilling, thus making it necessary to, lay out the holes, or their location, on only the uppermost member. Not only is a better jobsecured by this method but it is less costly to produce.

The usual method employed in fabricating structural elements is to drill or punch the holes in the different members separately and, accordingly, the rivets when driven, often do not entirely fill the holes because of the holes being out of alinement, thus permitting a bending strain to come upon the rivets instead of a mere shearing. Rivets are, of course, much stronger in shear than in bending.

An object is'to provide for clamping together the structural elements that are to be riveted so that the drilling can be effected and then the rivetingaccomplished while the elements are still clamped together as they were for drilling. r

Other objects and advantageswill appear in the subjoined detailed description.

' The apparatus disclosed in this application is not claimed herein but is the subject of a divisional application.

The accompanying drawings illustrate the invention: i

F ig. 1 is a plan View of: a drilling appara- 8, 1925. Serial No. 61,204.

tus that operates to perform the new method in accordancewith the provisions of this invention, the work that is to be drilled being indicated upon the work supports.

Fig. 2 is an enlarged side elevation of one of the work supporting carriages, a; girder being shown in broken lines supported on said carriage.

Fig. 3 is a plan section. V I g Fig. 4 is an end view of one of the carriages with means mounted'thereon for. aiding in turning of a structural steel element about its longitudinal axis, said element being indicated on the carriage in broken mes.

new of Fig. 2, partly in line indicated by 55, Fig.1, one of the movably mounted drills being shownin elevation.

F ig. 5 is a view, partly in section on the Fig. 6 is an edge View showing a number of clamps secured to a plate girder, which is indicated in broken lines.

I Fig. 7 is an endelevation of one ofthe clamps shown in Fig. 6.

carriage for supporting steel plates that are to be drilled.

Fig-.9 is a sectional elevation on the line indicated by 9-9, Fig. 8.

F ig. 10 is an enlarged broken sectional detail on the line indicated by 10 10, Fig. 9.

Fig. 11 is a sectional elevation on the line indicated by l111,-Fig. 8. ,7

Fig. 12 is an enlarged detail of the latch for couplingthe carriage to the operating cable. The form of the apparatus illustrated in Figs. 1 to 5 will first be described. it

In Fig. 1 a plurality of trucks or carriages Fig. 8 is a plan view of a modified form of 17 is shown, there being, in this instance, 7

two such carriages on each of the tracks 18. The work to be drilled may be. supported at its opposite ends on the two carriages on one track.

The carriages are moved toand fro on the tracks by the following described mechanism: An endless cable 19 runs between the tracks and around an idler sheave 20 at one end of the tracks and around other idler sheaves 21 adjacent to the other end of the tracks. Between two of the idler sheaves 21 is a rotatably mounted drum 22 around which a portion of the cable 19 is wound so 7 that turning of the drum will wind the cable at one side and unwind the cable at the axis of the carriage.

to the underside of the frame 3..

other side. The drum shaft23 is connected by suitable driving gear 24 to a motor 25.

The energizing circuit of the motor 25 is indicated at 26 and said circuit is opened and closed by amagnetic switch 27 controlled by a manually operated switch 28. It is not necessary to describe in detail the magnetic switch 27 and manually operated switch 28, herein, as these are well understood in the art relating thereto, and it suffices to state that the switch 28 may be operated so as to cause rotation of the motor25 clockwise or counterclockwise to drive the cable 19 in either direction.

Suitable means is provided for releasably coupling the cable 19 to the carriages 17 and, in this instance, said means is constructed as follows: Portions of the cable 19 are formed of chain links 29 and any one of the links is adapted to engage in a vertical slotBO in a standard or bracket 31 that projects upwardly at one side of the carria e. end 0 the standard 31. a

The links that are at opposite ends of the link that is engaged in the slot form shoulders 32 adapted to engage the standard 31 and thus prevent any appreciable relative movement between the cable and the carriagewhen the cable is coupled to said carria e.

In t iis instance, the standard 31 is secured to a movable member 33 pivoted at 34 to the frame 35 of the carriage. Means is provided for yieldingly holding the free end of the member 33 against longitudinal movement relative to the frame 85 and, accordingly, the member 38 passes through a plunger 36 that operates in a cylinder 37, the cylinder having longitudinally extending slots 38 to permit of movement of the member 33 lengthwise of the cylinder. At each end of the plunger 36 is a coil spring 39 within. the cylindeigsaid springs being of equal strength so as to balance the plunger in a midway position in the cylinder, in which position the member 33 is substantially at right angles to the longitudinal The cylinder 37 is fixed, being secured in any suitable manner \Vhen the drum 22 is started into operation to draw the cable 19 in either direction the appropriate spring 39 will yield to absorb the shock that would. otherwise be imposed upon the carriage in starting said carriage into motion.

In order to facilitate the drilling of some of the elements of relatively deep girders, each carriage frame 35 comprises longitudinal members 40 which, in this instance, are channel beams arranged in pairs, one pair for each side and the beams of each pair spaced to receive between them a pair of flanged wheels 41. Secured beneath and ex The slot 30 opens to the upper tending from one of the members 40 to the other are cross channel beams 42 with their webs uppermost. The girder to be operated on, indicated at a, rests on the beams 42. This construction of the carriages permits the girders to rest very low on the carriages and also to project as far as desired over the ends of the carriages, thus making it pos sible to use a shorter track than it the girder were supported in a manner to preclude it projectingbeyond both ends of the carriages.

When operating on beams or columns, it is frequently the case that it is desirable to turn the beam or column over upon the carriage between different drilling operations. Especially is it necessary to frequently perform this operation on H-beams, one of which is indicatedin difi'erent positions in full and in broken lines at b in Fig. 4. In order to effect the turning over of the beams and columns, the flexible member, in this instance a chain 43, of the hoisting tackle is wrapped around the beam Z), as clearly shown in Fig. 4, and a hook 44 secured to the end of the chain is hooked over the edge of one of thefianges of the beam, in this instancethe uppermost flange.

Cross members 45, which may be I-beams, are laid on the tops of the channel beams and oif of said members onto the ground.

The beam when thus turned, engages the abutments 46 and slides off of said abutments on to the cross members 45. This effects a quarter turn of the beam and the beam may be then turned another quarter of a turn by a similar procedure. Each time the chain 43 is drawn upwardly to rotate the column said column engages and slides down the abutments 46. By the means de scribed the columns can be turned very quickly by a single attendant who simply anchors the chain 4o around the column in the manner indicated in Fig. 4 and then has the chain; pulled upwardly by a suitable hoist, not shown.

To the cross members 45 having the abutments 46 there are secured, preferably,

abutments 48 which may be formed of angle fee are: preferably greased, -:the abutments 48 limit sliding of the beam Z) along the cross members away from the abutments 46.

When the Work is at rest on the beams 42, the cross members 45 will, of course, be removed. r

In fabricating the structural steel or iron members by the usual method, the members are marked at the points where the rivet holes, are to be made and the holes are then punched or drilled in each member separately. The members that areto be'riveted together are then placed with the holes for the rivets. approximately in alinement. The

alinement is generally inaccurate, in which event reaming of the holeis resorted to.

The misalinement is frequently so pronounced; that the reaming does not cure it.

The. rivets are then driven in the customary manner.

lVhen the holes in the member are not accurately alined and the. rivets are-driven,

said rivets donot perfectly fill. the rivet holes. In consequence, the connection is not such rivets .can occur.

so strong as it would be if the rivets perfectly filled the holes, because bending of Because of this nnperfection in fabricating structural steel, the

engineer who estimates the strength of the various members that are to form a. structure and, finally, to drive the rivets while the will be back to back.

members are still clamped together. Suitable clamps for this purpose are indicated,

in general, at 49 in Figs. 6 and 7. The

clamps are of identical construction and, therefore, only one will be described as follows:

Each. clamp 49 comprises spaced clamping members 50 and said members are longer than the width of the members that are to be assembled by riveting. These members 50 are connected together at their opposite ends by bolts 51. In connecting angle irons to a plate, indicated in broken lines in Fig. 7, the clamping-members 50 will be placed on opposite sides of the plate 52. Then the angle irons 53 will be placed in position at the edgesof the plate 52' so that the angle irons Then the bolts 51 will be tightened to clamp the members 50 against the edges of the outstanding legs of the angle irons. Screws 54 pass through the members 50 and each isprovided adjacent to the inner face of the member 50 with a nut 55. The

screws 54 can be shifted longitudinally of the members 50 because of the slots 56 in said 'members. The screws 54 will be positioned position to. another.

opposite the angle legs that are parallel with ,the plate 52 and the nuts will be turned tol clamp the screws 54 against the angle irons, thus securely clamping the plate 52 between the angle irons. The clamps 49will .beplaced at intervals along the member that is being fabricated, as indicated in F 6',

and then while the elements that constitute said member are clamped together, holes will be drilled at the designated places, and the rivets are then driven while the elements are still clamped together. After the rivets are" driven the clamps will be removed.

Though the drilling of the rivet holes may be effected in any suitable manner while the structural elements are clampedtogether. I

prefer to suspend the drill so that it may be moved freely over the work from one Referring more .especially to Fig. .5, the drill is indicated at 63 and is of any suitable construction, being in this instance an electrically driven drill of well known type. The drill is shiftably mounted, being provided with wheels 64 that run on a track 65. 4 In this instance the track 65 is movably mounted, being in the form of a boom that projects from a pivoting standard 66. This mountingof the drill is described in more detail and is claimed in my copending application for patent filed Octoher 8, 1925, Serial No. 61,205.. Said copending application also describes a hydraulic mechanism for raising and lowering of the drill. In Fig. 1 there is a plurality of the drills 63 with their mountings. The; booms are pivotally supported on opposite sides of. the tracks and each boom can be swung across bothtracks, thus enabling bot-h drills. to work simultaneously on a single girder or other long structural element.

The apparatus above described, in performing the new method, operates as .follows: Assuming, for example, that the girder a is being provided with cover plates, said cover plates, indicated at c, 0 will be temporarily clamped in place, by the use of any suitable clamps 67. The rivet positions will then be marked on the cover plates. The switch 28 will be properly operated to cause the trucks supporting said girder to run along the track to position the girder so that the drill or drills 63 can be brought to bear upon the marked rivet positions that are to bev drilled.

elements to which the plates are to be fastened. Then, while the cover plates are still clamped, rivets will be driven in the holes thus drilled and, finally, the clamps will be removed. While the girder is under construction, it may be necessary at times to more it along the track so, that the drill may be enabled to reachfar separated portions of the girder. At such times the The drill or drills will then be. operated to drill the requisite rivetholes .through the cover plates and the structural switch 28 will be properly operated to move the carriages as desired to ol, tainthisresult.

I have shown in Figs. 8 to 12, inclusive, a modilied form of carriage or truck for supporting the work that is to be drilled and for moving the work into dilfercnt positions. The parts that functionally correspond to those described for the carriagel? will be indicated by the same reference characteri's with the addition of the letter a thus avoiding a repetition of the description of structure that is the same for the carriage 17. This carriage 1T more especially designed for supporting plates that are to be drilled. The operating cable 19 has the chain 29 and said chain engages a slot 30 in a bracket or standard 31 that is secured to one end of a cylinder 37. A. similar standard may be provided at the other end of the cylinder. The slot 30 opens to the lower end of the standard 31 and, in order to prevent the chain 29* from slipping out of said slot, I

have provided a latch 57 in the form oi a hook which is plvoted at one end at 58 to the standard 31. The latch 57 is adapted to be swung into a vertical position to hook beneath the chain 29 when the chain is in the slot 80. The cylinder 37 is tree to move longitudinally in guides 59 which are secured to the frame In the cylinder 3? is a plunger 36 which is held stationary by a pin 60 passing through the plunger and fixed at its opposite ends in a bracket (51 formed of a pair of plates that are secured to and project down from cross members 2 of the frame 35. Positioned in the cylinder 37 at each end of the plunger 36 is a coil spring 39. The springs 39 are of the same strength so as to hold the cylinder 37 balanced. The operation of this device, when the cable 19 is pulled in either direction, is the same as previously described for the shock absorber illustrated in Fig. 3, excepting that, in this instance, the cylinder is yieldingly held by the springs against longitudinal movement so that the shock is transmitted by the rablc 19 to the cylinder and thence to either spring 39.

In the description of the operation of the invention, I have included the method oi fabricating structural elements since the elements are first clamped together, the rivet positions marked oil on one of the elements, holes drilled through the clamped elements at the marked positions and rivets driven in the holes while the elements remain clamped.

It is to be understood that before the clamps are removed, bolls may be passed through the holes drilled for the rivets and the nuts on said bolts drawn up tight so as to clamp the structural members together, whereupon the special clamps may be removed. Thus, in the appended claims, clamp and analogous expressions are to be understood as indicating the use of either the specialclamps or the bolts, just mentioned, whereby the structural members are temporarily clamped together while the holes are being drilled and the rivets driven in said. holes.

A variation of the above method may be pursued by interpolating,between the operations of clamping the elements and marking oil the rivet positions, the ope 'ations of tack welding the elements together at (lillerent points therealong and unclamping the elements. Such tack welding is indicated at 61 in Fig. 6 and it to be understood that the term tack welding employed herein delines the operation o'l making a weld of any suitable character at ('litl'erent spots or places whether only the metal of the welded elements constitutes the weld or other metal than that of the elements be usedin the weld. X

I claim:

1. The method of fabricating heavy columns, girders and other structural steel mem bers having center web plates and angle iron flanges, consisting of placing said angle iron flanges against the center web plate of the column or girder, clamping said angle irons to said column or girder web plate in finished position, drilling holes collectively through and throughsaid members while so bold, driving rivets through said holes, and removing said clamps;

The method of fabricating columns, girders and the like, consisting of laying a center web plate on a suitable support, placing angle irons against said web plate, clamping said angle irons to said web plate in the desired alignment, drilling holes collectively through and through said members, driving rivets through the drilled holes while drilling others, driving rivets after all the holes are drilled, and removing said clamps 3. The method of claln-icating columns, girders and the like, cons ting of laying a center web plate on a suitable support, plac- .ing angle irons against said web plate, clamping said angle irons to said web plate in the desired alignment, tack-welding said members together as aligned, unclamping the angleirons and web plate, drilling holes col lectively through and tl'n'ough said members, driving rivets through said holes.

il. The method of 'l alu'icating columns, girders and the like, consisting of laying a center web plate on a suitable support, placing angle irons against said web plate, clamping said angle irons to said web plate in the desired alignment, tack-welding said nuanbers together as aligned at intervals along said members, uuclamping the angle irons and web plate, drilling holes collectively through and through said members, driving rivets through said holes.

5. The method of fabricating heavy columns, girders andother structural steel members having center web plates and reinforcing members, consisting of placing said rereinforcingmembers to said column or girder web plate in finished position, drilling holes collectively throughand through said reinforcing member and center web plate while so held, driving rivets through said holes, and removing said clamps.

6. The method of fabricating heavy columns, girders and other structural steel members having center web'plates and angle stiffener bars, consisting of placing said angle stiffener bars against the center web plate of'the column or girder, clamping said angle stiffener bars to said column or girder web plate in finished position, drilling holes collectively through'and through said members while so held, driving rivets through said holes and IQIDOVHIO' said clam s. V a a 7. The method of fabricating heavy columns, girders and other structural steel members having center web plates and angle stiffener bars and filler plates, consistin of placing said angle stiffener bars and filler plates against the center web plate of the column or gird-er, clamping said angle stiffener bars and filler plates to said column or girder web plate in finished position, drilling holes collectively through and through said members while so held, driving rivets through said holes, and removing said clamps. I

8. The method of fabricating heavy columns, girders and other structural steel members having center web plates and angle iron flanges, consisting of laying a central web upon a suitable support, placing angle irons against the said central web, clamping said angle irons to said web plates in the desired position and in prop-er alignment, drilling holes through and through said members as held by said clamps, temporarily placing in said holes fastening members, removing said clamps, placing web stiffening angles and filler bars against said central web plate in proper alignment and desired position, and drilling holes through and through all said members in their assembled position, whereby said girder is prepared for the riveting operation, driving rivets through said holes and removing said fastening members from said holes.

- 9. The method of fabricating heavy columns, girders and other structural steel members having center web plates and angle iron flanges, consisting of laying a central web upon a suitable support, placing angle irons against the said central web, clamping said angle irons to said web plates in the desired position and in proper alignment, drilling holes through and through said members as held by said clamps, temporarily placing in said holes fastening members, removing said clamps, placing web stiffening angles andfiller bars against said central web plate in proper alignmentrand desired'position, and drilling holes through and through all said members in their assembled positions, placing cover plates onto the flange angle members of the girder and drilling holes through the'cover plates and the flange angles, whereby said girder is prepared for the riveting operation, and driving rivets through said holes.

10. The method of fabricating heavy columns, girders and other structural steel members having reinforcin elements, consisting of placing said reinforcing elements against a member of the column or girder, clamping said reinforcing element to said column or girder member in finished position, drilling holes collectively through and through said member and reinforcing element While so held, driving rivets through said holes, and removing said clamps.

11. The method of fabricating heavy columns, girders and other structural steel members having reinforcing elements, consisting of placing said reinforcing elements against a member of 'the column or girder, clamping said reinforcing element to said column or girder member in finished posi tion, drilling holes collectively through and through said member and reinforcing element while so held, placing temporary fastening members in said holes, removing said clamps, driving rivets through said holes, and removing said temporary fastening members.

Signed at Los Angeles, Calif. this 1st 

